[The intact, injured and repaired knee: in-vitro experimental biomechanics and level walking]

Published online: Jun 27 1992

B Landjerit, and M Thourot.

Laboratoire de Biomécanique, Ecole Nationale Supérieure d'Arts et Métiers, Paris, France.


In vitro simulation of knee joint movement during walking on flat ground was developed in this experimental study. Such movements are of interest for surgical and rehabilitation medicine in order to improve knowledge in the field of dynamic behavior of the knee joint during the entire range of motion: spatial kinematics and strains and stresses on the different components, in the case of intact knee, as well as of the operated one. As internal strains and stresses could not be measured directly, the aim of this experimental study was also to simulate such factors in a model using experimental input data. A simulator of joint flexion was built: it was composed of a hydraulic universal testing machine which allowed the main flexion-extension of the knee joint and an additional hydraulic device to impose the quadriceps extension force which represented the muscular action, synchronized with the imposed flexion-extension. The anatomical automatic passive rotation and valgus-varus motion were freely allowed, and these were measured during joint motion. In addition the lateral ligaments were fitted with strain sensors in order to measure their time-dependent behavior. The imposed flexion motion and quadriceps force were also measured to verify that they were accurately synchronized. The time-dependent values of force and flexion were taken from the literature. The analysis gave the mean result of eight reliable knee joint determinations: first of all intact, then after removing the anteroexternal cruciate ligaments, and finally after joint replacement by total knee prosthesis. One main conclusion was the comparison between automatic rotations, which decreased significantly after prosthesis surgery.(ABSTRACT TRUNCATED AT 250 WORDS)